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FPV drone v2 antenna upgrdes?
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djiuser_hxQscLQ4KJog
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Is there any companys out there that actaully make a better antenna for the V2 Goggles with a little more ranage then the stock ones. Also, how is it possablie to increase the RC singal too. I barely even get 1 mile in range out of both signals HD and RC.


Is it possablie on the next firmware update to boost the power form the software or is it already pushed to max form DJI?
5-29 23:28
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Buster1
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There are some goggle antennae that supposedly work better. I’m not sure of the company or who makes them, however they are not ‘official’ so use them at your own risk. As for the RC antenna, I haven’t seen anything, but that would be cool.

Where are you flying? I regularly get a mile or so range around my house (homes, trees, etc), and out over flat open terrain I’ve easily seen 2 miles range.
5-30 04:09
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luciens
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For the FPV drone, I'm pretty sure the RC link and video both are handled by the controller and not the goggles. So upgrading the antennas on the goggles won't make any difference - they just link to the controller, I believe.

For the air unit/caddx digital system, the transceivers in the goggles themselves definitely directly handle the video, so in that application better antennas might help. Reportedly the 5.8ghz patch antennas from iFlight, etc., significantly increase the quality of the video connection. But I haven't tried those on my V2 goggles.

I do know the range is pretty poor with the stock V2 antennas, especially with the DJI air unit at 700mw. The signal starts to degrade at about 1/2 mile and things get hazardous further than about 1 mile, even at the legal limit of 400' AGL altitude in a clear area. I've tried the 1200mw hack and that helps only a very little bit.

I'm tempted to try a set of the 5.8ghz patch antennas and dedicate one pair of my goggles to just the air unit/caddx, to see if I can make it any better.
5-30 05:33
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FrootWhoopz
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TrueRC makes replacement antenna's for the V2 goggles, they are called "Duality" because they are dual frequency (2.4 & 5.8ghz)
I was tempted to get them but I haven't found any reviews out there to show wether they really make enough of a difference.
5-30 15:40
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Duane Degn
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luciens Posted at 5-30 05:33
For the FPV drone, I'm pretty sure the RC link and video both are handled by the controller and not the goggles. So upgrading the antennas on the goggles won't make any difference - they just link to the controller, I believe.

For the air unit/caddx digital system, the transceivers in the goggles themselves definitely directly handle the video, so in that application better antennas might help. Reportedly the 5.8ghz patch antennas from iFlight, etc., significantly increase the quality of the video connection. But I haven't tried those on my V2 goggles.

"the RC link and video both are handled by the controller and not the goggles."

This is not the case. The video goes directly to the goggles.
5-30 15:53
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Duane Degn
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The YouTube channel RCSchim has a couple videos about the DJI FPV antenna. Here's one where he tests a few antenna.


It turns out the stock antenna from DJI are pretty good.
5-30 15:57
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luciens
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Duane Degn Posted at 5-30 15:53
"the RC link and video both are handled by the controller and not the goggles."

This is not the case. The video goes directly to the goggles.

I'd be quite surprised if that was the case. I'm pretty sure the goggles just link to the controller, which simply relays the video over that link. One way to confirm this is to turn your head when the drone is a ways away, and you'll notice no change in the signal strength. Even on 5.8ghz, the RSSI responds only to the orientation of the controller antenna, not the goggles.

5-30 16:49
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Stellios
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Buster1 Posted at 5-30 04:09
There are some goggle antennae that supposedly work better. I’m not sure of the company or who makes them, however they are not ‘official’ so use them at your own risk. As for the RC antenna, I haven’t seen anything, but that would be cool.

Where are you flying? I regularly get a mile or so range around my house (homes, trees, etc), and out over flat open terrain I’ve easily seen 2 miles range.

Actually right out my balcony. I live in a apartment building on the 10 th floor.
5-30 17:25
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Buster1
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luciens Posted at 5-30 16:49
I'd be quite surprised if that was the case. I'm pretty sure the goggles just link to the controller, which simply relays the video over that link. One way to confirm this is to turn your head when the drone is a ways away, and you'll notice no change in the signal strength. Even on 5.8ghz, the RSSI responds only to the orientation of the controller antenna, not the goggles.

Then how do you explain 4 bars for RC and 1-2 bars for video when I get far away and maneuver, or get low?
5-30 18:21
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Duane Degn
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luciens Posted at 5-30 16:49
I'd be quite surprised if that was the case. I'm pretty sure the goggles just link to the controller, which simply relays the video over that link. One way to confirm this is to turn your head when the drone is a ways away, and you'll notice no change in the signal strength. Even on 5.8ghz, the RSSI responds only to the orientation of the controller antenna, not the goggles.

"One way to confirm this is to turn your head when the drone is a ways away, and you'll notice no change in the signal strength."

That's not what I observe. When the video starts to go bad I make sure to point my goggles in the right direction and the video gets better.

Adding another video receiver and a video transmitter to the controller sure seems like a horribly inefficient way to move video around. All the video would be transmitted twice. The latency would be doubled. There's no way the controller is relaying the video. The video is transmitted by the drone and received by the goggles.

If the controller acted as a middle man, it would make sense to have the video recording done in the controller.

The antenna of the goggles are much more robust than the antenna of the controller. Here's a photo of the inside of the controller's antenna.


Requring the controller to retransmit video would be a horrible waste of processing resources and a needless increase of lanteny. Requiring the controller to retransmit the video would also require additional power.
5-30 19:38
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I use these as swear by TrueRC. I also use the stubby version for my traditional kwads. These are dual band to cover the FPV Drone. Really good range and had them on since delivery of the drone. No complaints at all - https://www.droneauthority.co.uk ... v-goggles-v2-4-pack
5-30 20:43
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FrootWhoopz Posted at 5-30 15:40
TrueRC makes replacement antenna's for the V2 goggles, they are called "Duality" because they are dual frequency (2.4 & 5.8ghz)
I was tempted to get them but I haven't found any reviews out there to show wether they really make enough of a difference.

I have used them since my drone was delivered. I already used the normal Stubby for DJI on my traditional FPV kwads. Brilliant in my experience. Good range and penetration.
5-30 20:45
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Hello there. Good day and thank you for reaching out.  Just a reminder that DJI does not recommend you to uses 3rd party accessories on your DJI Drones or modify your DJI product. These modifications might affect the said DJI drone when in use. There is a possibility that these modifications will be able work. However, since it's not optimized and tested by DJI we cannot guaranteed the stability of the said 3rd party accessory or modifications if it will work all the time with no issues and might void the warranty of the said DJI product. Thank you and have a safe flight always.
5-30 21:43
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luciens
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Buster1 Posted at 5-30 18:21
Then how do you explain 4 bars for RC and 1-2 bars for video when I get far away and maneuver, or get low?

The video feed, or a part of it at least, always appears to be on the 5.8ghz band. Even if you force it to 2.4ghz in the goggle menu, something is still happening on 5.8ghz. That's why the penetration of the video is still poorer than the R/C link even on 2.4ghz.

Of course, the exact protocol and bands used are all proprietary, but that seems to be the case. Ian (madrc) has looked at it on a spectrum analyzer on his youtube channel, but I can't seem to find the link to the video right now.

Another poster looked at the transmission from the goggles when connected to the FPV drone and noted that it's still only transmitting on 5.8ghz all the time. It may be receiving on 2.4 or 5.8 depending on the setting, though.
5-31 04:51
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luciens
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Duane Degn Posted at 5-30 19:38
"One way to confirm this is to turn your head when the drone is a ways away, and you'll notice no change in the signal strength."

That's not what I observe. When the video starts to go bad I make sure to point my goggles in the right direction and the video gets better.

Nevertheless, that seems to be what it's doing. This is how the old DJI goggles worked on Ocusync 2.0 when connected to the mavic pro 2, for example. The back-and-forth to the aircraft was all done through the controller.
There's no latency with a repeater - it's just a retransmission of a received signal on another frequency, there's no digital processing of the RF involved. It's a tried-and-true method that can be done with all analog circuitry in radio that's been around forever.

I also don't observe the variation in the RSSI with head position with the FPV drone that you're seeing. When using an Air Unit/Caddix vista, etc., where the transceivers in the goggles are clearly being used directly for comms with the air unit, the effect is dramatic when you reorient the goggles with respect to the aircraft. You just don't see that with the FPV drone.

As for the antennas, even 2.4ghz antennas are pretty small - the ones in your pictures may look like they're dinky, but they're not. They appear to be simple dipoles, more or less the same type of antennas in the V2 goggles. There's nothing wrong with the dipole - it's a tried-and-true simple antenna that's probably still the most common type of antenna in general.

Keep in mind also that the antennas on the FPV drone itself are much better than the arrangement on the Air Unit or Caddix Vista, etc. It has 4 of them, presumably offering full diversity transcieve on both bands.

Course, this is mostly speculation, since exactly what's going on with the video/RC link on the FPV drone is known only to DJI. But clearly the remote is handling the lion's share of comm back and forth to the drone itself and not the goggles.
5-31 05:02
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cootertwo
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I LOVE this stuff! I've spent many hours, wondering how this DJI digital stuff is working. I got hooked on the FPV kit (have 2), and started buying Vista and air units, to convert some of my older builds. However, I found a BIG difference between the new FPV drone, and the now, older Vista/Air units. Not near the range, or quality. Sure, much better than my best analog, but not near the same as the FVP drone setup. Is it the Occusync3 ??? So many questions. So many controllers, video units, cameras.... on and on
5-31 05:39
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luciens
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cootertwo Posted at 5-31 05:39
I LOVE this stuff! I've spent many hours, wondering how this DJI digital stuff is working. I got hooked on the FPV kit (have 2), and started buying Vista and air units, to convert some of my older builds. However, I found a BIG difference between the new FPV drone, and the now, older Vista/Air units. Not near the range, or quality. Sure, much better than my best analog, but not near the same as the FVP drone setup. Is it the Occusync3 ??? So many questions. So many controllers, video units, cameras.... on and on

Well part of it is the much better antenna arrangement on the FPV drone, and part of it is the significantly higher power of the transmitters on both the drone and the controller. The drone's max radiated power is around 1.4 watts, which is double the normal max of 700mw on the DJI air unit and caddix (on 5.8ghz only). Though there's a simple hack to increase the transmitter power output to 1.2 watts.

The remote is also capable of 1.4 watts radiated power on 5.8ghz, where I believe the video transmission takes place at all times with the FPV drone.

Also, simple dipole antennas are used throughout on the FPV drone, from what I can see, on the aircraft and on the remote. The Air Unit and Caddix usually come with LHCP antennas, whereas on the V2 goggles, the stock antennas are dual-band dipoles. So there's a little bit of loss there, due to the different polarization. Not a lot, but there is a little bit.  But on the FPV drone, the antennas on the aircraft and on the remote are oriented similarly, so you don't have losses associated with different polarization.

So, the RF situation with the FPV drone is just a much better design, so that's why it has so much more range and reliability than the goggles + Air Unit.
Course, this is all just my observation by looking at the equipment on both. DJI may be doing other things that nobody knows about to make the RF connection on the FPV drone better, so there may be other stuff going on.  


5-31 06:16
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Buster1
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luciens Posted at 5-31 05:02
Nevertheless, that seems to be what it's doing. This is how the old DJI goggles worked on Ocusync 2.0 when connected to the mavic pro 2, for example. The back-and-forth to the aircraft was all done through the controller.
There's no latency with a repeater - it's just a retransmission of a received signal on another frequency, there's no digital processing of the RF involved. It's a tried-and-true method that can be done with all analog circuitry in radio that's been around forever.

Luciens, you’re obviously pretty smart on this stuff, but I’m still not believing that the RC is handling any drone-transmitted video. This is due to the following two reasons:

1. The arrangement of the 4 goggle antennae are arranged in such a way, to imply signal reception from multiple azimuths. Other antennae in the world are sometimes arranged like this for receiving signals from multiple airborne azimuths. Why would goggle antennae be engineered like this if the goggles were only receiving signals from the RC?

2. I can turn off my RC controller, and still see what the drone is seeing in the goggles and often have 4 bars of video strength, with a Red RC indication.
5-31 07:08
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luciens
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Buster1 Posted at 5-31 07:08
Luciens, you’re obviously pretty smart on this stuff, but I’m still not believing that the RC is handling any drone-transmitted video. This is due to the following two reasons:

1. The arrangement of the 4 goggle antennae are arranged in such a way, to imply signal reception from multiple azimuths. Other antennae in the world are sometimes arranged like this for receiving signals from multiple airborne azimuths. Why would goggle antennae be engineered like this if the goggles were only receiving signals from the RC?

Well that would be a good test - take the drone out to about 2 miles and shut off the remote . I'm too afraid to try it, but you may be right. That'd be a good way to see.

But unquestionably, the controller is contributing in some way, since it has transceivers for both bands, and is capable of 1.4 watts EIRP on 5.8ghz. So it has to be playing some significant role in the video link... Maybe telemetry or something like that?
5-31 07:35
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luciens
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As for the arrangement of the antennas on the goggles, they were put that way originally on the V1’s presumably to optimize use with the air unit. There wasn’t an FPV drone when the goggles were designed the first time. I suppose they kept it like that in the V2’s since they support the air unit also.
5-31 11:48
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Stellios
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luciens Posted at 5-31 06:16
Well part of it is the much better antenna arrangement on the FPV drone, and part of it is the significantly higher power of the transmitters on both the drone and the controller. The drone's max radiated power is around 1.4 watts, which is double the normal max of 700mw on the DJI air unit and caddix (on 5.8ghz only). Though there's a simple hack to increase the transmitter power output to 1.2 watts.

The remote is also capable of 1.4 watts radiated power on 5.8ghz, where I believe the video transmission takes place at all times with the FPV drone.

what's the simple hack?? Most of the hacks out there that I have tried don't work. There is a company that sells some app that puts the drone in FCC mode but that hack works for the Euro people but here in the USA there's really no hack that's worth it for us here in the USA.

I'd like  it if DJI would just give us the option in the Manu settings to do this.
6-1 23:29
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Stellios Posted at 6-1 23:29
what's the simple hack?? Most of the hacks out there that I have tried don't work. There is a company that sells some app that puts the drone in FCC mode but that hack works for the Euro people but here in the USA there's really no hack that's worth it for us here in the USA.

I'd like  it if DJI would just give us the option in the Manu settings to do this.

The one I’m referring to is for the Air Unit / caddx, not the FPV drone. Search on DJI 1200 mw hack and there’s a couple vids that show how to do it. For the FPV drone, I’m not familiar with it hat hack but if you have the US model, it’s already in FCC mode….
6-2 08:20
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Raf_IZ0QWM
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Hi guys,
I did various tests with the DJI FPV and with the transmitter.
In addition, on the internet you will also find the reports that DJI had to send for FCC certification.
On these reports, for those who are radio communications experts and work in the field, there is a lot written about what you want to know.

DJI FPV goggles receive and transmit. They receive an OFDM transmission ranging from 10 to 40MHz.
And they transmit an ACK from time to time whose band size is between 1.5MHz and 3MHz.
The remote control sends signals of similar size.

The Ocusync 3.0 uses 4-antenna MIMO technology on the drone.
I have not disassembled it but judging by how the remote control antennas are, it is presumable that the drone antennas are two with vertical polarization (the forward ones) and two with horizontal polarization (the rear ones).

The antennas of the goggles are linear polarization like all those used on this drone.
In addition, they are installed at a slight angle to improve reception and also pick up the horizontal or vertical signal.
Two antennas transmit and receive and two receive only.

I'm sorry but I made a video only in Italian in which I show that the DJI goggles also transmit at 2.4GHz because many in Italy, due to a video of a youtuber, did not believe it and thought they could use the antennas of the goggles V1 also on V2.

Here the S11 image of the goggles antenna. I'm sorry I don't have the photo of the VSWR measurement ... which is actually not good at all, especially at 2.4GHz (But also because during the measurement the ground plane is different from the original one on the goggles)

http://www.kwos.org/droni/DJI_FPV_antenna_goggles_02.jpeg

I plan to build better performing antennas.

Ah a key thing is that since the goggles also send the acks on reception, it is important that the drone knows that the video is being received. That is with the FPV system, if you do not receive the video you go blind and there is no reason to have a controller that goes further than the goggles.

In my opinion it is very important that the goggles receive well because only they receive the largest (widest) data flow and therefore the one that first interrupts for the distance.
The wider the bandwidth, the smaller the distance reached will be because for the same watt of the transmitter, the power will be distributed over a wider channel, which is why the antennas of the goggles must be as good or better than those of the remote control.

That's the video:


What else can I tell you ... DJI used folded dipoles as antennas.
Obviously, those of the goggles, have the ground plane on the goggles themselves, so they are half folded. While the remote control and the drone use folded.

6-2 12:19
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Duane Degn
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Raf_IZ0QWM Posted at 6-2 12:19
Hi guys,
I did various tests with the DJI FPV and with the transmitter.
In addition, on the internet you will also find the reports that DJI had to send for FCC certification.

"it is presumable that the drone antennas are two with vertical polarization (the forward ones) and two with horizontal polarization (the rear ones)."

The drone has six antenna plus the GPS antenna. I think two of the antenna on the drone are used to receive ADS-B data. Here's the (I believe ADS-B) antenna on the right side of the drone. The right edge of the antenna is parallel with the front of the drone (where the camera attaches). The bottom edge of the antenna is just above the front right arm. These side antenna connect to the PCB which also contains the GPS module.
DjiAntennaSide.jpg

Here's a photo of the PCB antenna inside the left front leg of the drone. The antenna trace runs down the front edge of the PCB. There's a 100mm trace on the other side of the PCB which is located under the edge antenna trace. I forgot to photograph this trace while taken these other photos. The three LEDs seen in the top right of the photo are pointed out the back under the front left motor.

DjiAntennaRear.jpg

There are antenna running horizontally inside the rear arms. I don't see a way to access these antenna. Thanks for sharing so much great information. I have one of my two drones taken apart right now. Let me know if there are any parts you want photographed. I plan to take photos of all the various parts and add these photos to my Hackday.io project. I'm hoping to build the parts of this DJI drone into an alternate frame. I don't expect my Frankenstein drone to perform any better than the original drone but I think it will be interesting to see a conventional drone frame with DJI FPV parts.
6-2 18:44
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Raf_IZ0QWM
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Duane Degn Posted at 6-2 18:44
"it is presumable that the drone antennas are two with vertical polarization (the forward ones) and two with horizontal polarization (the rear ones)."

The drone has six antenna plus the GPS antenna. I think two of the antenna on the drone are used to receive ADS-B data. Here's the (I believe ADS-B) antenna on the right side of the drone. The right edge of the antenna is parallel with the front of the drone (where the camera attaches). The bottom edge of the antenna is just above the front right arm. These side antenna connect to the PCB which also contains the GPS module.

Oh yes,
the drone also have 2 antennas for the ADS-B as it works on two frequencies:
ADS-B 1090 e UAT 978

A friend of mine sent to me a photo of a broken rear arm


6-2 20:28
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Duane Degn
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Raf_IZ0QWM Posted at 6-2 20:28
Oh yes,
the drone also have 2 antennas for the ADS-B as it works on two frequencies:
ADS-B 1090 e UAT 978

"A friend of mine sent to me a photo of a broken rear arm"

Thanks for sharing the photo. I was curious about the internal antenna.
6-3 06:16
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Raf_IZ0QWM
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Duane Degn Posted at 6-3 06:16
"A friend of mine sent to me a photo of a broken rear arm"

Thanks for sharing the photo. I was curious about the internal antenna.

I asked to him to open the arm...I would like to see the dipole.
6-3 06:54
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Stellios
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Raf_IZ0QWM Posted at 6-3 06:54
I asked to him to open the arm...I would like to see the dipole.

i just crashed my drone last night and ordered another one. I was thinking of taking mine apart to see how it works I can send you all the pics you want
(its not saveable, 2 broken arms and 2 broken motors and lost the gimble somewhere in the crash.)
6-4 23:51
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Stellios
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here u go brother
AC8F3CA9-64D2-42C8-9EBB-228165A62633.jpeg
4815DF76-D8DF-4F34-8FC8-83421AC25F41.jpeg
6-5 00:50
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Stellios
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pretty bad crash too already ordered another one and i should have it by monday next week.
B7E05C86-0FA0-4E5A-BDF5-A1243FE7902C.jpeg
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6-5 00:52
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Raf_IZ0QWM
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Thank you boy!  It's a normal dipole with linear polarization
6-5 13:55
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Duane Degn
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Wow, you managed to rip some of the LEDs off the PCB.

The front antenna can be seen by removing the covers. The rear antenna are the ones hidden deep inside. I'd love to see more photos of the rear antenna. Don't destroy your rear arms to do this. They are likely worth a bit of money if they're still intact. I'd also like to see photos of the internal LEDs in the arms.

Thanks for sharing photos of the carnage.
6-5 14:19
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Stellios
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The only thing that savable was the impact sensors in the front even the two arms in the back have tiny little cracks. I hit a tree at around 30 m in height and I was pretty heavy into the throttle but when I try to pull up my gimbal wasn’t very level and then by the time I leveled it in the middle of flight it was already too late and there’s a tree. My speed was around 65mph when I smacked the tree lol
6-5 15:00
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6-6 00:43
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anethema
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Raf_IZ0QWM Posted at 6-2 12:19
Hi guys,
I did various tests with the DJI FPV and with the transmitter.
In addition, on the internet you will also find the reports that DJI had to send for FCC certification.

Cool info for sure. I just got some True RC dualities coming. Going to leave the linears on the bottom and the new ones on the top. They are circular polarized and in some tests I've seen seem to do a bit better than the stock linears.

Can you confirm the antenna ports are in this config?
6-6 15:15
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Raf_IZ0QWM
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Yes, I can confirm that the configuration you see in the figure is the one I experienced.

On the fact of using the TrueRC here, surely the original antennas do not have a good tuning, in particular at 2.4GHz but be careful, when you measure them, you never have the same ground plane that they would have resting on the glasses.

Today I take them back to the office and measure the VSWR which indicates how well they are tuned to the frequency.

And if we want to talk about making goggles work with circular polarization antennas, I suggest you read this article:
https://mimosa.co/white-papers/antenna-polarization-2

the antennas are inclined precisely because since the drone has two antennas in vertical polarization and two in horizontal, thus holding them they are able to "see" the signal in both polarizations.

The drone therefore uses a mixed type polarization (read in the article)

as you can read, a mix of linear and
6-6 20:29
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anethema
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Raf_IZ0QWM Posted at 6-6 20:29
Yes, I can confirm that the configuration you see in the figure is the one I experienced.

On the fact of using the TrueRC here, surely the original antennas do not have a good agreement, in particular at 2.4GHz but be careful, when you measure them, you never have the same ground plane that they would have resting on the glasses.

I work in radio so pretty familiar with polarization.

While I agree that linear to linear SHOULD be better, either the effective gain, or just the constant fading between vertical to horizontal to slant as the thing flies around, seems to result in the TrueRC antennas working better.

Hard to explain exactly what is going on without some tests I can't really perform, but in practice there are quite a few videos on youtube of people testing the DJI FPV drone with the TrueRC antennas, and in all of them they get longer range signal performance than the stock antennas.

And do be fair the max loss from circular to linear is 3dB which you will probably be getting with the linears pretty often as they rotate through space.

Either way, def interested to give it a shot.
6-6 22:31
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Raf_IZ0QWM
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anethema Posted at 6-6 22:31
I work in radio so pretty familiar with polarization.

While I agree that linear to linear SHOULD be better, either the effective gain, or just the constant fading between vertical to horizontal to slant as the thing flies around, seems to result in the TrueRC antennas working better.

I work in the field of radio communications, too. Satellite communications.

There are a few things to consider:

A circular polarization antenna if it receives the signal only of a linear polarization antenna (eg vertical) loses 3dB
But if it receives the MIMO signal from two linearly polarized antennas, both vertical and horizontal, then you have + 3dB -3dB which is 0dB of loss and so it can work.
This is the same when using multiple 45 ° slant antennas and linear polarization antennas.

TrueRC antennas work better than the original ones because they are calibrated much, much better than the original ones.
The original antennas have SWR greater than 2 at 2.4GHz. Today I post an image.
While TrueRC antennas have a SWR of almost 1.
This means that with the original antennas a part of the transmitter PWR is lost in heat and is not radiated in the antenna.

Another reason is that the drone does not always travel in a straight line and chooses the antennas with which to transmit depending on the signal it receives from the goggles and the remote control.

The drone also has 2TX / RX and 2RX. The front antennas are vertical and the rear ones horizontal. As the MIMO auto adapts to the received signal, with the circular polarization antennas on the goggles, he will transmit with 1 antenna vertically and 1 horizontally which will be the best system.
However, it may happen that on some occasion he transmits and receives in the same polarization and here the antennas in circular will lose ....
However, the MIMO of the drone is dual band and so ... maybe, it will move from one band to another and everything will be fine again.

To say that an antenna and a configuration are better you need to make some measurements. First on one band and then on the other.

It would be nice to turn all the drone antennas into circular!

6-7 00:00
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Raf_IZ0QWM
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So, today I've done some more test with the goggles antennas and with one home made.

This is the VSWR of the original antenna:


This is the VSWR of the home made antenna:


This is the very rough setup.
I didn't have the TX test room available:


The results:

2400MHz Original


5800MHz Original


2400MHz Home made antenna


5800MHz Home made antenna


I would like to do a similar thing with the TrueRC antennas...
6-7 07:41
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Raf_IZ0QWM
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DJI Stephen Posted at 5-30 21:43
Hello there. Good day and thank you for reaching out.  Just a reminder that DJI does not recommend you to uses 3rd party accessories on your DJI Drones or modify your DJI product. These modifications might affect the said DJI drone when in use. There is a possibility that these modifications will be able work. However, since it's not optimized and tested by DJI we cannot guaranteed the stability of the said 3rd party accessory or modifications if it will work all the time with no issues and might void the warranty of the said DJI product. Thank you and have a safe flight always.

Thank you Stephen,
in fact, it is assumed that those who modify the drone in some part of it know what they are doing.
But you know it well ... we always try to do something to fix, touch, disassemble what we have. They are our toys and they are beautiful for that too.

Thank you for your active participation in the forum.

Raf
6-7 07:54
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